Badidi Bouda A., Halimi R., Benzohra M., Lebaili S.

ABSTRACT In this paper we are proposing an experimental study of the effect of low alloy steels carbon rate on the velocity and propagation attenuation coefficient of the ultrasonic waves in these materials. We have observed simple relations between the velocities and the attenuations according to the carbon rate. The same observations can be made for the Young modulus. These results, in conformity with the theory, show the possibility of characterizing the carbon rate by a nondestructive method: ultrasounds. In parallel we have studied the effect of some heat treatments such as hardening, annealing and quenching on velocities and attenuations. The results obtained show a correlation between heat treatments and ultrasonic parameters[1,2] . This opens ways to a more complete and nondestructive characterization of materials by ultrasounds methods. [1] A. Badidi Bouda A. Benchaala & K. Alem Ultrasonic characterization of materials hardness, Ultrasonic, vol.38, 2000, pp224-227 [2] A. Badidi Bouda, S. Lebaili & A. Benchaala, Grain Size Influence On Ultrasonic Velocities and Attenuation, NDT&E International, January 2003 Key Words: ultrasonic, grain size, hardness, elastic constants, HAZ , attenuation, velocity.